Shift Tower & shift lever

pinball73

Senior Member
Got a question about the shifter tower on my 29! started having a bit of trouble with it jumping out of gear when decelerating going down hill. my question is , is the part of the gear shifter lever that engages the shifting forks supposed to be round or flat on all four sides? another question is how can you check to see if the shifting forks are straight? they show some wear where the shift lever engages them! can you buy new ones or do you have them refurbished. the rest if the transmission is new except the case.
 
I gave my shift lever and forks to a local machine shop and had them welded/ground back to spec. I recommend giving the lever and the forks to the same welder, to prevent a situation where they both get welded up so much they no longer mesh together.
 
Which gear is it jumping out of? High or 1:1 drive will generally stay in mesh. 2nd gear can get to be problematic if there is too much play in the counter shaft cluster or if there is too much play in the main output shaft. Excessive gear tooth or spline wear can also be a problem. The shift fork rod detents or spring in the tower can also wear out and be a problem holding the shift fork rods in place
 
Attached are several articles that may be of help.

Tom Endy


Oh boy have I ever got some work ahead of me! I am going to need to find some one who can weld & then turn the ball back down. the shifting forks will not be a problem I don't think! there is a shop hear that can weld the worn places & mill it back to specs. I wonder if a guy could use one of the shafts that hold the shifter forks & make it a true right angle on a peace of flat steel & check the forks for being straight? reason being i don't have a fork that I know is not bent!
Thanks for the help
 
I've found more than one shift lever ball that was brazed up and contoured with a file. The spherical part is 1/2" diameter. The tip of it is more of a cylindrical shape and smaller. Trying to turn a spherical shape on a lathe is difficult but the shape of the lever makes it impossible. Where there is a will, there is a way. The grinder jig looks like someone formed a 1/2" radius into the grinding wheel. I wonder how they trued the grinder wheel?
 
Which gear is it jumping out of? High or 1:1 drive will generally stay in mesh. 2nd gear can get to be problematic if there is too much play in the counter shaft cluster or if there is too much play in the main output shaft. Excessive gear tooth or spline wear can also be a problem. The shift fork rod detents or spring in the tower can also wear out and be a problem holding the shift fork rods in place


it is jumping out of third gear going down hill! there is no excusive slack that I can find! every thing in the transmission is new! the only thing I didn't do is rebuild the shifting tower, until now & I am in the process of dong this as we speak.
 
I've found more than one shift lever ball that was brazed up and contoured with a file. The spherical part is 1/2" diameter. The tip of it is more of a cylindrical shape and smaller. Trying to turn a spherical shape on a lathe is difficult but the shape of the lever makes it impossible. Where there is a will, there is a way. The grinder jig looks like someone formed a 1/2" radius into the grinding wheel. I wonder how they trued the grinder wheel?


believe it or not I found a place in my little town that has done this type of repairs on this sort of thing before! I think a 8n ford tractor is set up just like this! the guy has a good machine shop & said it is no problem, he has done it before.
 
Be sure the flywheel cover is dialed in, and be make sure the input shaft bearings are good, as well as the bushing or bearing in the end of the crankshaft (pilot bearing).
 
Be sure the flywheel cover is dialed in, and be make sure the input shaft bearings are good, as well as the bushing or bearing in the end of the crankshaft (pilot bearing).


I dialed the flywheel cover when I rebuilt the motor & I also replaced the pilot bearing at that time. at a later time I removed the transmission, & I have all new gears & bearings in the transmission. this is just a wild thought! do you think it would be possible to push the pilot bearing out while installing the transmission? the reason I mention this is I never had this problem before, till I removed & rebuilt the transmission! I did not remove or mess the the clutch, just the transmission
 
I dialed the flywheel cover when I rebuilt the motor & I also replaced the pilot bearing at that time. at a later time I removed the transmission, & I have all new gears & bearings in the transmission. this is just a wild thought! do you think it would be possible to push the pilot bearing out while installing the transmission? the reason I mention this is I never had this problem before, till I removed & rebuilt the transmission! I did not remove or mess the the clutch, just the transmission


Doubtful but anything is possible. With all the work you did, I would feel confident saying that rebuilding the tower will fix your jumping out of gear problem.
 
The one to one drive locks the input shaft to the output shaft. This connection could be where the problem is. The 2nd/high gear doesn't engage the input shaft all that much since it just dogs on there. Deceleration and especially down hill puts an engine brake load on the drive train. When this happens, the gears, splines, & drive line components start to ride on the opposite surfaces from where they do under acceleration. This is a different strain on things and it can change thrust loads inside the transmission and rear axle. If the input shaft can move too much, it may cause a decouple of the 1:1 drive. If the gear is sloppy on the shift fork or main output spline then that can have an affect.

You can generally feel if the shift lever detents are working. It takes a bit of a push or pull to overcome them. If they feel OK than that might not be the problem.
 
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Found these pictures, not sure of who posted them but very informative.
 

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Fixture I made for removing shifter spring.
 

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Fixture I made for removing shifter spring.



Thanks for the pictures! I built one something like this only I used a 1 1/4" pipe about 7" long & cut about a third out of one side about 3" long & welded a round washer on the end of the pipe I had cut out & cut a slot in it to insert in the spring. put a flat plate on the opposite end with two holes for bolts that go down to the tower. it seems to work pretty good
 
Found these pictures, not sure of who posted them but very informative.


thanks for the pictures! I was thinking of something along these lines to check the forks to see if they were straight, as I do not have a fork that I know is straight to match them too.
 
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